Slot unit



Nnv. 2 192e. 1,605,528

T. w. cAsE v sLo'nxJNiT y Filed May '7. 1925 y Patented Nov. 2, 1926.

vUNITED STATES t 1,605,528 PATENT OFFICE..

THEODORE WILLARD'CASE, OF AUBURN, NEW YORK, ASSIGNOR TO CASE RESEARCH LABORATORY INCORPORATED, OF AUBURN, NEWVYQRK, A CORPORATION OF NEW SLOT UNIT.

-.4LPplimmfm' med nay 7,-1925. .serial No. 28,620.

This vinvention relates to-a certain new and improved apparatus for taking, printing or reproducing a film record, and is particularly designed for use in producing a film record of light -variations as caused by electrical variations preferably correspondl ing to sound wave variations, as for instance, articulate sound waves, and the method of producing such apparatus.

In apparatus of this character for producing or reproducing a lilm record of light variat1ons,'it has been customary to move the film past a small printing slot in a Wall disposed between the film and a source of light, and. is essential that the film move past the-slot in tight contact with the Wall -so that .only the portion of the lm directly in front of the slot is exposed to the light emanating from the source. A

Considerable diiiiculty has been experienced in producing ah' accurateclear and exact film record, and also in reproducing accurately the original sound from a record due to the factthat dust, filmanaterial or foreign matter collects in the slot,-more particularly is scrapedoff the film record as it passes by the edge of the slot, and this foreign material partially obstructs the slot which is extremely small, as for illustration, .0015 of an inch vinwidtli and .1 of an inch in length. And the result is that thefilm reco-rd produced is somewhat unsatisfactory because of this obstruction ofthe slot, andL for the same reason a reproduction of even a perfect film record is unsatisfactory and the object of this invention'is the production of an apparatus retaining all the advantages of present similar apparatus, but in which this disadvantage is avoided.

More especially 'this invention'is addressed to the production of a slot-containing unit of novel construction, and adapted for use in either picture-taking or picture-reproducmethod of producing such slot-.containing unit. Y

Other objects-and advantages relate to the details of the structure for effecting the main )object of this invention, andhto the particular method of vproducing the same, all as will more fully appear from the followingdescription, taken in connection with the accompanying drawings, in Which:'-

Figure 1 is' a diagrammatic illustration of an apparatus for producing a lm record mg apparatus, 'as above set forth, and to the of lightA variations as produced by electrical variations corresponding to articulate sound waves or musical tones.

Figure 2 is an elevation of a portion of the slot-containing unit.

' Figure 3 is a longitudinal section through the slot containing unit as illustrated in Figure 2.

Figure 4 is a vertical section through the slot-containing unit illustrated in Figure 2.

Figurev 5 is a diagrammatic illustration'of an apparatus for reproducing sound Waves from a film recrdl F igu'ref-'- isfa view similar to Figure 4 of a modified formofslot unit. 4

In 'a general way, the structure of Figure 1 is the same asthat disclosed in my application. Serial N o. 719,098 filed June 10, 1924, and comprises a variable source'of cathode rays including two spaced electrodes 2* and -3`- enclosed in a bulb -1-, the elec- .,trodes being connected-'in' circuit with a source of poteiitialV as a battery '-4- and a secondary -5- of a transformer, the pri! mary 6 of which isconnected in circuit with a source of otential '-7- acrossthe filament -'8- an plate-Q of a space discharge device l0- the grid -11 of which is connected in circuit with the fila-4 ment -S-and the secondary v'--39- of a transformer, the primary 4lof which is connected in circuit with a source of potential, .lk

In a general Way, this structure includes means for varying an electric currentv in accordance with sound wavefvariations and for amplifying such variations, and thereby effecting amplified variations in the source of light -1-, the`light rays emanating from which are adapted to be printed or photographed upon 4thefilm n13 moving past the narrow slot 14rin the slotcon taining unit -15-. This Aslot-containing unit -15- may be a portion' of an enclosure for the film, or a portion ofen-enclosure for the` lamp, and takes thel place of the ordinary portion of Va photographing leo apparatus or reproducingapparatus, which contains the usual slot past which it is'quite essential that .the film should move in tight relation with the walls bordering the slot.

This slot-containing unit is of novel manfacture and construction, and as here shown, consists of a sheet of transparent 4materialas the quartz or glass sheet -16- of any suitableV shgpe.- and size.- Upon one face of the glass plece -'16- there is formed a layer -17- off metal preferably produced insuch a. way that the metal is strongly ad- This layerl hered to the quartz or glass. of metal may perhaps preferably be evaporated upon the quartz-- or glass, or may be electrically de osited thereon so as to form preferably a t in coating or sheet of metal upon one side of and firmly adhered to the surface of the glass plate.

Any suitable metal may be utilized for thisy purpose, but I have found silver effects a satisfactory result. A very thin layer of silver is highly efficient for my purpose. In the drawings, it has been desirable to greatly exaggerate the thickness of the component parts for the purpose of clarity.k

Vhen the thin coating of metal has been produced upon the glass in any suitable manner as for instance, one of those described, a small portion of the metal is scraped off the quartz or glass so as to eX- pose a portion of the glass plate through the metal and this may be effected in any suitable way as by a diamond point or the like, so as to produce a slot or opening through'the metal of a proper length and Width, a size suitable for this purpose being .0015 of'an inch in Width and .l of an inch in length.

After a sharply defined slot -l4. as described has been formed through the thin metal coating -17-, then the metallic layer or coating or a portion of the same and the quartz or glass disclosed through the narrow elongated slot -14 is covered with a layer -l8 of transparent material substantially filling the slot, and covering the surrounding metallic surface so as to form a continuous unbroken surface. Preferably a. coating of a bakelite lacquer or varnish (a condensation product of phenol and formaldehyde) is formed on the metallic layer, or a portion of the same, and across and in the slot so as to fillA or partially fill the latter and form a substantially continuous even or unbroken surface which becomes extremely hard and smooth when baked.

The present preferred process consists in spraying or atomizing under pressure bakelite lacquer upon the metallic coating and the quartz exposed through the slot so as to form a thin layer -18- of lacquer and then baking the lacquer to firmly unite it to the metallic coating and form a transparent hard smooth surface.

The metal layer is preferably of such extreme thinness that any inequality in the surface conformation of the baked lacquer layer, which results from the filling of the slot -14 with the lacquer, is of inconsequential character. i

It Will 'appear from this description'that the slot containing unit described consists vantages are obtained by applying the slot filling and covering layer in liquid form as by spraying under pressure upon the metallic layer, and then reducing the same-- to an eXtreme hardness as by baking, and for these reasons bakelite lacquer is peculiarly adapted for my process and the product.

In Figure the slot-containing unit is constructed in the same manner as that described in connection withI Figs. l to 4 inclusive, but for the particular use there illustrated, viz,`the reproduction of talking pictures, the light from the suitable source as lampv -20- passes through the slot -14- formed in the metal layer -17- also passing through the glass or quartz member -16- and the layer -18- of baked bakelite lacquer and then passes through the film -21- Whichconstitutes the sound record and strikes the light sensitive cell -22- which may beformed of any suitable material that varies its resistance in accordance with the intensity of the light to which it is subjected, yas for instance, l selenl um. v

The light cell Q2- may, as shown, be connected in circuit with a suitable source of potential as battery Q4- across the filament w-25- and grid 26- of a space discharge device -27-, the filament -25- and plate -28- of Which device are connected in circuit with a source of potential as battery -29-, and a translating device as the telephone receivers -30-.

For the purpose ofl compensatingy for variation in light cells as manufactured,or-

other varying conditions, a potentiometer 3l-'- and a fixed resistance 3Q-fmay be placed across the filament and grid of the electron discharge device --27.

In Figure 6 the quartz or glass member -l6- is rounded or formed as a portion of a cylinder with the metallic layerV on the exterior of the cylindrical surface and the bakelite lacquer layer upon the surface of the metallic layer and in the slot in the same manner as heretofore described. In forming the unit, this construction may have certain advantages due to the fact that the film will move in tight relation with the unit only at points adjacent the slot.

It will be obvious that by the method described a slot-containing unit is formed adapted tol take the place of the usual slot member and havin0' a or the adjacent portion of any structure that incorporates such a slot, and through whic the light is adapted to pass to a film in a substantially unobstructed manner, while at the same time the entry of foreign matter to the slot is prevented either by the scraping of the lm'across as in the usual structure, or otherwise, and altho I have shown and described a s ecific structure asillustrative of an embo iment of my invention which is at present perhaps g f to the opaque layer and the transparent backreferred, I do not desire to restrictmysel to the details of' the structure or the particular materials from which the same is formed, or to the exact form and relation of the parts, in the scope of the appended claims.

I claim:

l. In an apparatus of the character described, a transparent member, anopaque gr member 1n contact with the transparent slot therethrough, and a transparent acquer filling the slot and coverinvr the adjacent surface of the opaque mem er.. l v

2. In an apparatus of the character described, a transparent member, an opaque member in contact with the transparent member and secured thereto and having a slot therethrough, and a hard smooth baked transparent lacquer lling the slot.

3. In an apparatus of the character described, a transparent member, an opaque member in contact i with the transparent member and having a slot therethrough, an a transparent condensation product of ph nol and formaldehyde filling the slot and covering the member. -l

4. In an apparatus of the character described,"a glass member, a thin metallic layer secured to the glass member and having a slot extending through the layer, parent laquer filling the ladj acent surface of the metallic layer.

5. InI 'an apparatus of the character described, a glass member, a thin metallic layer secured to the glass member and having a s lot extending through the layer, and a hard smooth baked transparent lacquer lling the slot and covering the adjacent surface ofthe metallic layer.

6. In an apparatus of the character?? described, a glass member, a thin metallc layer the edge of the slot as various changesmay be made withadjacent surface of the opaque gr and a trans the slot and covering secured to the glass member and having a parent condensation product of phenol and formaldehyde lling the' slot and covering the adjacent surface of the metallic layer.

' 7 The" method of vproducing a slot unit comprising forming a layer of an opaque material upon a transparent background with a narrow elongated.` slot through the opaque layer to expose the transparent backround, then applying a transparent lacquer ground exposed through the slot, and bakingthe lacquer.

8. The method of producing va slot unit comprising forming a layer of an opaque ,material upon a transparept backgroun withl a narrow elongated slot through the opaquelayer to expose the transparent backound, and then applying a liquid capable of becoming hard and transparent to the surface of the opaque material and the transparent background exposed through the slot. 9;"lhe method of producing a slotunit comprising forming a layer of an opaque material upon a `transparent backgroun with a narrow elongated slot through the opaque layer to expose the transparent background, and then atomizing a liquid upon the`surfacf`e of the opaque(d tansparent background exposed through the s ot. I

l). The methodL of producing a slot unit comprising forming la opaque layer to expose the transparent backound, and then applying bakelite lacquer to the transparent background exposed through the slot and the adjacent portions of the opaque material.

' l1. The method of producing a slot unit layer of an opaque material upon a transparent background with a narrow elongated slot through the opaque layer to expose thetransparent background, and then atomizing .a bakelite lacquerupon the surface of the opaque material and the transparent background exposed through the slot.

' In witness whereof I havehereunto' 4set my hand this 39th day of April 1925.

material and the h slot extending through the layer, and a trans- I layer of an opaque d material upon a transparent .background with a narrow elongated slot through the v j 'rHEoDoRE WTLLARD CASE. l 

